A drone delivery venture called Zipline International is coming out of stealth mode with backing from big-name investors and a humanitarian mission in mind.

During a Bay Area demo broadcast via Periscope, Zipline CEO Keller Rinaudo and other executives showed how they plan to use mini-planes launched with compressed air to deliver blood and medical supplies in Rwanda starting in July.

Zipline has been working on a fleet of 15 electric-powered, GPS-guided Zip drones for a couple of years, but the startup has been flying under the radar (so to speak) until this month.

Rinaudo says the San Francisco startup has raised $18 million in funding from investors including Microsoft co-founder Paul Allen, Yahoo founder Jerry Yang, Sequoia Capital, Google Ventures and Stanford University. (Much of that investment came during Zipline’s previous incarnation as Romotive.) Zipline’s employees are said to include aerospace engineers from NASA, SpaceX, the Boeing Co. and Lockheed Martin.

Rwanda will serve as a test case for a “drone port” system that’s designed to get emergency supplies quickly to areas where the roads are hard to negotiate. The planes can range as far as 35 miles from their port, drop off a package weighing up to 3.5 pounds, then return to base autonomously, Zipline says.

Company executives told The Associated Press that the cost of each flight is about the same as the cost of a less reliable motorcycle trip.

“Our partnership with Rwanda is just the beginning,” Zipline says on its website. If the Rwandan experiment goes well, the medical delivery program could be extended to other countries.

Zipline isn’t the first venture to experiment with using drones for humanitarian purposes.

A map shows Zipline’s plan to deliver blood and medical supplies to a region of the central African country of Rwanda. (Credit: Zipline)

In the United States, a startup named Flirtey has been conducting tests of emergency drone deliveries with the Federal Aviation Administration’s approval. But Zipline isn’t planning to break into the U.S. drone delivery market anytime soon.

“The U.S. has one of the most complicated airspaces in the world, and for that reason the FAA is even more risk-averse than most regulators,” Rinaudo, whose LinkedIn page lists a stint as a professional rock climber, told AP. “So I think where this will start is in environments where the need is incredibly high and the airspace is relatively empty.”

Besides, Amazon, Walmart, Google and other deep-pocketed players are already deeply into preparations to enter the U.S. drone delivery market. The FAA is expected to issue its rules for commercial drone operations this spring.

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